America's Orchids - Fairy Slipper

Fairy slipper (Calypso bulbosa) is sometimes called Venus' slipper, Calypso orchid, deer's head orchid, and angel slipper. The fairy slipper is found in northern hemisphere regions around the globe, but is rare is some areas. In the U.S., this native orchid is protected in Arizona, Michigan, New Hampshire, New York, Vermont, and Wisconsin.

Fairy slipper has a one green leaf that appears near the ground and is 1 to 2 inches long. There is a single flower, 3/4 inch wide and 1/2 to 1 inch long, with a white cup that is tinged with purple and shows definite lines, three upright sepals, and two narrow petals in a deep pink to pale purple. The stem is 2 to 8 inches tall. Once the flower fades and dies, the leaf will also die. Fairy slipper grows from a bulb-like corm which has fibrous roots. Next year's corm will begin from this year's corm, and the sequence of corns will persist on the plant for several years. Most colonies of fairy slipper contain only a few plants.

Fairy slipper is monoecious and relies on bees for pollination. Reproduction is seed. Seedlings are rarely seen in the Great Lakes region of the country. Seedlings are more common in the western States in high country.

Most fairy slippers require several mycorrhizal fungi in the protocorm (microscopic first-development stage of growth of an orchid from seed) tissue for successful germination. This fact means that cultivation of fairy slippers is difficult unless the specific soil fungi are available. Some research indicates that there is reproduction by way of rhizomes. In western states, corms have commercial value; they are dug and exported.

Fairy slipper prefers moist, shaded soil in swamps, bogs, and along bodies of water. Look for this orchid in coniferous areas where there are decaying leaves and wood on the ground. The fairy slipper sometimes grows at the base of trees and in the decayed pockets of dead trees. It is possible to locate fairy slipper only when it is bloom. The plants can remain dormant for up to two years.

The blooming period can last for two to fives months, from March through July, depending on the area. In California and the Pacific Northwest, bloom time is March through June. In Michigan and the rest of the Great Lakes area, it is from late-May through June.

Early people in British Columbia tribal groups were known to value the corms as a food source.

The fairy slipper has predators. It is subject to attack by rodents, slugs, and fungi. If the flower is picked, or if the plant is stepped on, death will soon follow.

As with most native wild flowers, it is illegal to pick orchids from public forest areas.

Sources
Calypso bulbosa, USDA Forest Service, http://www.fs.fed.us/database/feis/plants/forb/calbul/all.html
Calypso bulbosa, Michigan State University, http://web4.msue.msu.edu/mnfi/abstracts/botany/calypso_bulbosa.pdf
Calypso bulbosa, Robert W. Freckmann Herbarium, University of Wisconsin, http://wisplants.uwsp.edu/scripts/detail.asp?SpCode=CALBULvAME
Calypso bulbosa, Southwest Colorado Wildflowers, http://www.swcoloradowildflowers.com/Pink%20Enlarged%20Photo%20Pages/calypso%20bulbosa.htm